Low-profile optical mounting assembly

ABSTRACT

In an ocular support assembly material present in the forward-looking cross-section of the outwardly extending support arms is removed, thereby reducing visual obscuration and enhancing peripheral vision. In the preferred embodiment, the top of each outwardly extending support arm is at or below the middle of the height of the housing, thereby resulting in a low-profile design. At the same time, the support arms are received by the housing with sliding engagement on all sides, thereby eliminating the need for ball bearings or spacers to counteract twisting. The result is a lightweight yet highly stable ocular mounting assembly.

FIELD OF THE INVENTION

This invention relates generally to ocular mounting assemblies of thetype use in surgical, medical and dental applications and, inparticular, to a stable, low-profile assembly affording enhancedperipheral vision.

BACKGROUND OF THE INVENTION

Telescopic instruments are widely used for magnifying a work area duringprecision work such as delicate surgery, dental work, inspection ofcircuit board solder joints, and assembly of miniature parts. A typicaltelemicroscopic instrument includes a pair of telemicroscopic loupeswhich are adjustably mounted to an eyeglass frame or headband. Thetelescopic loupes combine the long working distance of the telescopewith the high quality magnification of the microscope. This type ofoptical instrument provides the user, a surgeon, for example, with amagnified image of the work area with a field of view at about an arm'slength.

As one example, the ocular mounting assembly disclosed in U.S. Pat. No.5,381,263 allows the mounting of a pair of ocular devices to an eyeglassframe, or head mount, and is linearly or rotationally adjustable throughfive degrees of freedom. An adjustable ocular support assembly withslidably extendable arms provides interpupillary distance, convergenceangle and view adjustment of the ocular devices, which are rotatableattached to the support. An adjustable hinge/slide mount assembly isrotatably attached to the ocular support assembly and provides heightand view angle adjustment of the ocular devices. When the slidable armsof the ocular support assembly are extended, however, some rotatingmotion may occur, in particular with heavier oculars and with fullyextended support arms. The rotating motion causes vertical misalignment,or divergence, of the axes of the ocular devices. Excessive divergencecan cause eyestrain, discomfort and even headaches.

U.S. Pat. No. 6,333,814 improves upon the above design by providing apair of stabilizers disposed inside the assembly housing and providingstability against rotational motion when the arms are extended. In oneembodiment, the stabilizers are interference-fitted balls, retained inposition by retainer holes in the assembly housing, and receding intorecess cut-outs at the end of the support arms when the arms are fullyretracted. In an alternate embodiment, the stabilizers are L-shaped, andcan be either an integral part of the housing or bonded to it withadhesive.

Despite these advances, existing designs tend to be physically ratherbulky, limiting peripheral vision, for example, when the practitionerlooks away from the loupes. FIG. 1 is a drawing that shows front and topviews of an older rack assembly, including a housing 20 into whichsupport arms 22 are slidingly engaged to set interpupillary distanceusing adjusting knob 24. The oculars 14 are attached to the arms 22through pivots 32 which may be adjustable or fixed in position for agiven working distance. A rearward extension 34 having side pinsinterconnects to a pivot assembly (not shown) which, in turn, may beaffixed to eyeglass frames or a headband mount. These features are shownin the issued patents referenced hereinabove. Note that in this olderdesign, the front of the housing 20 is a considerable distance d1 fromthe front of the oculars, and the height of the side arms 22, h1, isnearly equal to the top of the housing 20, resulting in portions havinga relatively large cross-section directly above the eyes of the user. Assuch, when the user looks away from the oculars 14, these extensions ofthe support arms tend to get in the way.

FIG. 2 shows a somewhat newer design, wherein the pivot points 32′ arepushed back on the oculars, allowing the distance d2 to be shortenedsignificantly. However, in this case, the cross-sections 22′ of theoutwardly extending support arms are nearly the same height as thehousing 20′, leading to continual visual obscuration.

SUMMARY OF THE INVENTION

This invention improves upon prior-art ocular support assemblies byremoving material present in the forward-looking cross-section of theoutwardly extending support arms, thereby reducing visual obscurationand enhancing peripheral vision. In the preferred embodiment, the top ofthe outwardly extending support arm is approximate to the middle of theheight of the housing, thereby resulting in a low-profile design. At thesame time, the support arms are received by the housing with slidingengagement on all sides, thereby eliminating the need for ball bearingsor spacers to counteract twisting. The result is a lightweight yethighly stable ocular mounting assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing of an older style ocular mounting assembly;

FIG. 2 is a drawing of a relatively new ocular mounting assembly;

FIG. 3 is a drawing of a mounting assembly configured in accordance withthe present invention;

FIG. 4A is a top-view drawing of the ocular mounting assembly of FIG. 3with the support arms retracted, showing the way in which gear meshingoccurs; and

FIG. 4B is a top-view drawing of the ocular mounting assembly of FIG. 3with the support arms extended.

DETAILED DESCRIPTION OF THE INVENTION

Having discussed FIGS. 1 and 2, the reader's attention is directed toFIG. 3, which shows an ocular mounting assembly constructed inaccordance with the invention. The housing is shown at 320, including anoutwardly extending portion 334 having side pins that engage with ahinged pivot assembly (not shown), which may be similar to, if notidentical to, prior-art hinge assemblies facilitating an eyeglass orhead-band mount. The adjustment knob is shown at 324, and the ocularsare shown at 314.

Importantly, according to the invention, the top surface 350 of eachsupport arm 322 has material removed, allowing the top of the supportarm to be at or below the horizontal centerline 352 of the housing 320.This removed material decreases visual obscuration and enhancesperipheral vision for the user. In the preferred embodiment, thedimension between the top of the arms major length to the area directlyabove the ocular is 0.099″+/−0.010″ (2.51+/−0.25 mm). The dimension fromthe top of the rack housing to the area directly above the ocular is0.149″+/−0.015″ (3.78+/−0.38 mm).

FIG. 4A is a top-view drawing illustrating the inner workings of theinvention, with support arms 322 each having narrower portions 402, 404including teeth with mesh gear 406. The gear 406 is, in turn, coupled tothe adjustment valve 324 to facilitate interpupillary distanceadjustment. Another important aspect of the invention, however, is thatthe portions of the support arms between the ocular mounting pads andthe portions 402, 404 with teeth are substantially rectangular, suchthat all four side surfaces of the support arms are slidingly engaged bythe rectangular openings of the housing 320, thereby preventingtwisting. Although portions X are relieved to reduce weight, theanti-twisting design is not defeated.

Note that the oculars may be independently rotatable about axes 332, orthey may be fixed at a particular convergence angle as disclosed incommonly assigned U.S. Pat. No. 6,704,141. The dipvergence adjustmentsof U.S. Pat. No. 6,439,714 may also be employed.

1. An ocular mounting assembly, comprising: a housing having a backsurface and a hollow through-bore with a height and opposing open ends,each with an inner wall; a pair of support arms, each slidingly receivedby a respective one of the open ends; each support arm having an outerportion extending from the housing; each outer portion having a bottomsurface adapted for coupling to an ocular loupe and an upper surface;and wherein the upper surface of each support arm is approximately halfthe height of the housing.
 2. The ocular mounting assembly of claim 1,wherein each support arm includes a central portion with an outersurface that is substantially flush with the inner surface of thehousing to minimize twisting.
 3. The ocular mounting assembly of claim1, wherein each support arm includes an inner portion disposed entirelywithin the housing, each inner portion including a plurality of teeththat engage with a central gear coupled to an external knob to adjustfor interpupillary distance.
 4. The ocular mounting assembly of claim 1,wherein back surface of the housing includes an extension adapted forpivotal coupling to a spectacle or headband mount.
 5. An ocular mountingassembly, comprising: a housing having a back surface and a hollowthrough-bore with a height and opposing open ends, each with an innerwall; a pair of support arms, each slidingly received by a respectiveone of the open ends; each support arm including: an inner portionincluding a plurality of teeth that engage with a central gear coupledto an external knob to adjust for interpupillary distance, an outerportion having a bottom surface adapted for coupling to an ocular loupeand an upper surface, and a central portion having upper and lowersurfaces between the inner and outer portions; and wherein the uppersurface of the central portion transitions downwardly to the uppersurface of the outer portion.
 6. The ocular mounting assembly of claim5, wherein the upper and lower surfaces of the central portion aresubstantially flush with the inner surface of the housing to minimizetwisting.
 7. The ocular mounting assembly of claim 5, wherein the backsurface of the housing includes an extension adapted for pivotalcoupling to a spectacle or headband mount.
 8. The ocular mountingassembly of claim 5, wherein the upper surface of each support arm isapproximately half the height of the housing.
 9. An ocular mountingassembly, comprising: a housing having a back surface and a hollowthrough-bore with a height and opposing open ends, each with an innerwall; a pair of ocular loupes; a pair of support arms, each slidinglyreceived by a respective one of the open ends; each support armincluding: an inner portion including a plurality of teeth that engagewith a central gear coupled to an external knob to adjust forinterpupillary distance, an outer portion outer portion having an uppersurface and a bottom surface coupled to a respective one of the ocularloupes, and a central portion having upper and lower surfaces betweenthe inner and outer portions; and wherein the upper surface of thecentral portion transitions downwardly to the upper surface of the outerportion.
 10. The ocular mounting assembly of claim 9, wherein the upperand lower surfaces of the central portion are substantially flush withthe inner surface of the housing to minimize twisting.
 11. The ocularmounting assembly of claim 9, wherein back surface of the housingincludes an extension adapted for pivotal coupling to a spectacle orheadband mount.
 12. The ocular mounting assembly of claim 9, wherein theupper surface of each support arm is approximately half the height ofthe housing.